ISEKAI JA SLOW LIFE WA MAMANARANAI: SEIJUU NO SHUJIN WA SHIMA SODACHI

Natsume Ren, raised on an island, loses his life when he tries to save a child in a rough sea and is swept away by the waves. However, after death, he meets the god who governs reincarnation and learns that he was not meant to be born on Earth, and is reincarnated as Lyle in the other world where he was originally meant to be born. Lyle lives a loving life with his new family, and when he turns three, he is reunited with his beloved dog from his previous life, Amon! It turns out that Amon had followed Lyle across the boundaries of the world and arrived in this land, becoming a sacred beast. Lyle wants to live a peaceful life in this other world with his dog and family, but he gets caught up in various incidents, and his path to a slow life is proving to be quite difficult...!? (Source: AlphaPolis, translated) — Description from AniList community (anilist.co).